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The aim of the present study was to compare serotyping, PFGE and AFLP for typing of Streptococcus pneumoniae with regard to discriminatory power, typeability and typing system concordance. Thirty-four isolates from cerobrospinal fluid and 34 time-matched blood culture isolates collected from in-patients at two hospitals in western Norway during the period from January 1994 to May 2002 were included in the study. The discriminatory powers of serotyping, PFGE and AFLP were 0.93, 0.99 and 0.95, respectively. The typeabilities for serotyping, PFGE and AFLP were 1, 1 and 0.99, respectively. A good concordance was shown between all the typing methods. Serotyping would most probably have a higher discriminatory power if further subtyping had been performed. PFGE was more discriminatory than AFLP, and AFLP grouped more-distantly related isolates together. The two typing methods thus provided different information, and therefore both could be useful adjuncts to serotyping for the characterization of S. pneumoniae.

Herpes simplex viruses types 1 and 2 (HSV-1 and HSV-2), which are common worldwide, are so similar that antibodies directed against one serotype may crossreact with antigens from the other one. Methods for specific detection of antibodies against HSV-1 or HSV-2 are based upon the antigenicities of glycoproteins G. However, due to the cost, the available commercial methods may not readily be used in developing countries. A different enzyme-linked immunosorbent assay (ELISA) method, based upon a synthetic oligopeptide corresponding to an immunogenic region in glycoprotein G of HSV-2, has been used recently and successfully for detection of HSV-2 antibodies. In the present study, the sequences of a newly identified immunogenic and type-specific region in glycoprotein G of HSV-1 was used to synthesize three different, branched oligopeptides. The performances of these peptides in an ELISA were investigated by testing Scandinavian and African sera which were characterized by commercial ELISA and Western blotting methods and divided into four groups either lacking HSV antibodies, containing antibodies against one or the other virus, or against both types. The peptide which corresponded in sequence to the immunodominant region was as specific and sensitive by an ELISA as were the commercial methods. The method is inexpensive and reliable.

Extended-spectrum beta-lactamases (ESBLs) were present in high proportions of Escherichia coli (25% [9 of 36]) and Klebsiella pneumoniae isolates (17% [9 of 52]) causing pediatric septicemia at a tertiary hospital in Tanzania. Patients with septicemia due to ESBL-producing organisms had a significantly higher fatality rate than those with non-ESBL isolates (71% versus 39%, P = 0.039). This is the first report of the CTX-M-15 genotype of ESBLs on the African continent and the first observation of SHV-12 genotype in an isolate of Salmonella enterica serotype Newport.

Treatment of asymptomatic bacteriuria and urinary tract infections in pregnancy can prevent adverse outcome for mother and child. However, antimicrobial resistance can impede effective chemotherapy. From April 1995 to March 1996, urine specimens from 5153 pregnant women in a rural area in northern Tanzania were inoculated on dip slides. Bacterial isolates from 101 positive dip slides were identified and tested for susceptibility to antimicrobial agents by disc diffusion. In total, 107 bacterial isolates were recovered, 71 Gram-negative and 36 Gram-positive. The most frequent isolates were Escherichia coli (n=27) and enterococci (n=15). E. coli isolates showed low rates of resistance to ampicillin (17%), mecillinam (9%), cefalexin (0%), nitrofurantoin (4%), trimethoprim-sulfamethoxazole (0%), trimethoprim (13%) and sulfamethoxazole (0%). Other Gram-negative bacteria displayed higher rates of resistance to these drugs. All enterococcal isolates were sensitive to ampicillin and only 2 were resistant to nitrofurantoin. Growth of E. coli from urine culture was correlated with adverse outcome of pregnancy (relative risk 4.13, 95% confidence interval 1.50-11.38). Antimicrobial susceptibility prevails in urinary isolates of E. coli and enterococci from rural areas of northern Tanzania. Susceptibility data from both rural and urban areas should be taken into account when planning antibiotic policies.

The urgent need to treat presumptive bacterial or fungal infections in neutropenic patients has meant that initial therapy is empiric and based on the pathogens most likely to be responsible, and drug resistance. The traditional empirical treatment in Norway has been penicillin G and an aminoglycoside, and this combination has been criticized over recent y. We wished to analyse the microbiological spectrum and susceptibility patterns of pathogens causing bacteraemia in febrile neutropenic patients. This was a prospective multicentre study. During the study period of 2 y, a total of 282 episodes of fever involving 243 neutropenic patients was observed. In 34% of episodes bacteraemia was documented. Overall, 40% of the episodes were caused by Gram-positive organisms, 41% by Gram-negative organisms and 19% were polymicrobial. The most frequently isolated bacteria were Escherichia coli (25.6%), a- and non-haemolytic streptococci (15.6%), coagulase-negative staphylococci (12.4%) and Klebsiella spp. (7.4%). None of the Gram-negative isolates was resistant to gentamicin, meropenem, ceftazidime or ciprofloxacin. Only 5 coagulase-negative staphylococci isolates were resistant to both penicillin G and aminoglycoside. The overall mortality rate was 7%, and 1.2% due to confirmed bacteraemic infection.

Background: Antimicrobial resistance is particularly harmful to infectious disease management in low-income countries since expensive second-line drugs are not readily available. The objective of this study was to implement and evaluate a computerized system for surveillance of antimicrobial resistance at a tertiary hospital in Tanzania., Methods: A computerized surveillance system for antimicrobial susceptibility (WHONET) was implemented at the national referral hospital in Tanzania in 1998. The antimicrobial susceptibilities of all clinical bacterial isolates received during an 18 months' period were recorded and analyzed., Results: The surveillance system was successfully implemented at the hospital. This activity increased the focus on antimicrobial resistance issues and on laboratory quality assurance issues. The study identified specific nosocomial problems in the hospital and led to the initiation of other prospective studies on prevalence and antimicrobial susceptibility of bacterial infections. Furthermore, the study provided useful data on antimicrobial patterns in bacterial isolates from the hospital. Gram-negative bacteria displayed high rates of resistance to common inexpensive antibiotics such as ampicillin, tetracycline and trimethoprim-sulfamethoxazole, leaving fluoroquinolones as the only reliable oral drugs against common Gram-negative bacilli. Gentamicin and third generation cephalosporins remain useful for parenteral therapy., Conclusion: The surveillance system is a low-cost tool to generate valuable information on antimicrobial resistance, which can be used to prepare locally applicable recommendations on antimicrobial use. The system pinpoints relevant nosocomial problems and can be used to efficiently plan further research. The surveillance system also functions as a quality assurance tool, bringing attention to methodological issues in identification and susceptibility testing.

Background: Clinicians at Haydom Lutheran Hospital, a rural hospital in northern Tanzania noted an unusually high case-fatality rate of pediatric meningitis and suspected an outbreak of an unknown agent or an organism resistant to the empirical therapy., Methods: We established a provisional microbiology laboratory to investigate the suspected outbreak. Blood and spinal fluid specimens were taken from children below the age of seven years with suspected meningitis. The blood and spinal fluid specimens were inoculated in commercial blood culture bottles and locally prepared Thayer-Martin medium in slanted tubes, respectively. The bacterial isolates were sent to Norway for further investigation, including susceptibility testing and pulsed-field gel-electrophoresis (PFGE)., Results: Among 24 children with suspected meningitis and/or septicemia, five neonates had meningitis caused by Salmonella enterica serotype Enteritidis, all of whom died. Two children had S. Enteritidis septicemia without meningitis and both survived. Genotyping with PFGE suggested a clonal outbreak. The salmonella strain was resistant to ampicillin and sensitive to gentamicin, the two drugs commonly used to treat neonatal meningitis at the hospital., Conclusion: The investigation reminds us that nontyphoidal salmonellae can cause meningitis associated with very high case-fatality rates. Resistance to multiple antimicrobial agents increases the risk of treatment failure and may have contributed to the fatal outcome in all of the five patients with salmonella meningitis. The investigation indicated that the outbreak was nosocomial and the outbreak subsided after hygienic measures were instituted. Establishing a provisional microbiological laboratory is a valuable and affordable tool to investigate and control outbreaks even in remote rural areas.

Rapid and accurate identification of carriers of resistant microorganisms is an important aspect of efficient infection control in hospitals. Traditional identification methods of antibiotic-resistant bacteria usually take at least 3 to 4 days after sampling. A duplex real-time PCR assay was developed for rapid detection of ampicillin-resistant Enterococcus faecium (ARE). Primers and probes that are used in this assay specifically detected the D-Ala-D-Ala ligase gene of E. faecium and the modified penicillin-binding protein 5 gene (pbp5) carrying the Glu-to-Val substitution at position 629 (Val-629) in a set of 129 tested E. faecium strains with known pbp5 sequence. Presence of the Val-629 in the strain set from 11 different countries was highly correlated with ampicillin resistance. In a screening of hospitalized patients, the real-time PCR assay yielded a sensitivity and a specificity for the detection of ARE colonization of 95% and 100%, respectively. The results were obtained 4 h after samples were harvested from overnight broth of rectal swab samples, identifying both species and the resistance marker mutation in pbp5. This novel assay reliably identifies ARE 2 to 3 days more quickly than traditional culture methods, thereby increasing laboratory throughput, making it useful for rectal screening of ARE. The assay demonstrates the advantages of real-time PCR for detection of nosocomial pathogens.

Background: Patients with polio often experience new symptoms (muscle weakness, pain, fatigue and respiratory problems) many years after the acute disease. This study examined possible interactions between lifestyle factors (overweight, physical inactivity, smoking) and late polio with new symptoms., Methods: A total of 148 patients hospitalized for acute polio in 1950-1954 at Haukeland University Hospital, Norway and 128 patients, hospitalized for acute polio in 1958 at Tartu University Hospital, Estonia responded to a mailed questionnaire regarding lifestyle and late polio with new symptoms. Multiple regression analysis, two samples t-test and chi-square analysis were undertaken., Results: Mean body mass index (BMI) and percentage of smokers did not differ in the two cohorts, while polio patients were physically less active in Estonia. The physically active patients in both cohorts had significantly lower odds for experiencing polio-related late muscle pain (OR = 0.21; 95% CI = 0.08-0.55) and fatigue (OR = 0.32; 95% CI = 0.14-0.75). With increasing age the patients had significantly higher odds for experiencing new muscle weakness (OR = 1.03; 95% CI = 1.00-1.07), fatigue (OR = 1.04;95% CI = 1.01-1.07) and breath shortness (OR = 1.04; 95% CI = 1.00-1.07)., Conclusion: Physically inactive patients are at a higher risk for late polio-related symptoms. An active lifestyle should be recommended for patients with polio sequels.

Reliable molecular methods for determination of relatedness between bacterial isolates have become increasingly important to evaluate outbreaks and endemic situations with nosocomial pathogens. In the present study Simpson's index of diversity with calculated confidence intervals was used to compare amplified fragment length polymorphism (AFLP) and pulsed field gel electrophoresis (PFGE) analysis of a hospital outbreak of ampicillin-resistant Enterococcus faecium and subsequent endemicity. The outbreak, in a Norwegian tertiary hospital, of infections caused by these enterococci started in 1995 and increased in 1996 after which the situation turned endemic. The purpose of this study was to compare the two methods in this setting and to determine the length of time during an outbreak that these methods are sufficiently valid to be of value for hospital infection control efforts. One hundred and sixty clinical isolates from urine specimens collected during the period 1995-1999 were included. The findings indicate that PFGE and AFLP are equally discriminative and could in this setting be used for typing purposes over the whole 5-year period.

To assess the validity of the reference values for hematologic and immunologic indices currently used in Africa, we evaluated blood samples from 3,311 human immunodeficiency virus (HIV)-negative Ugandans aged 1 week to 92 years. Erythrocyte, hemoglobin, and hematocrit levels and mean corpuscular volume all significantly increased with age (P < 0.001) and were independent of gender until the age of 13 years, after which the levels were higher in males than in females (P < 0.001). White blood cell, neutrophil, lymphocyte, basophil, and monocyte counts significantly declined with age until the age of 13 years (P < 0.001), with no differences by gender, while platelet counts declined with age (P < 0.001) and showed differences by gender only among adults older than age 24 years. CD4+- and CD8+-cell counts declined with age until the age of 18 years; thereafter, females had higher counts than males. The absolute values for many of these parameters differed from those reported for populations outside Africa, suggesting that it may be necessary to develop tables of reference values for hematologic and immunologic indices specific for the African population. This may be particularly important with regard to CD4+-cell counts among children because significant differences in absolute and percent CD4+-cell counts exist between the values for Western populations and the values for the population evaluated in our study. These differences could influence the decision to initiate antiretroviral therapy among children infected with HIV.

Poliovirus (PV) subjected to genetic characterization is often isolated from faecal carriage. Such virus is not necessarily identical to the virus causing paralytic disease since genetic modifications may occur during replication outside the nervous system. We have searched for poliovirus genomes in the 14 fatal cases occurring during the last epidemics in Norway in 1951-1952. A method was developed for isolation and analysis of poliovirus RNA from formalin-fixed and paraffin-embedded archival tissue. RNA was purified by incubation with Chelex-100 and heating followed by treatment with the proteinase K and chloroform extraction. Viral sequences were amplified by a reverse transcriptase-polymerase chain reaction (RT-PCR), the products subjected to TA cloning and sequenced. RNA from the beta-actin gene, as a control, was identified in 13 cases, while sequences specific for poliovirus were achieved in 11 cases. The sequences from the 2C region of poliovirus were rather conserved while those in the 5'-untranslated region were variable. The developed method should be suitable also for other genetic studies of old archival material.

The genetic relationship of 81 ampicillin-resistant and 21 ampicillin-susceptible Enterococcus faecium isolates from clinical infections and rectal screening in hospitalized patients in Norway was studied by pulsed-field gel electrophoresis (PFGE) and amplified fragment length polymorphism (AFLP). PFGE showed 55 different banding patterns, and 65 of the isolates could be grouped into one large group. With AFLP, 46 patterns were discerned, and 74 isolates clustered in one group. In general, the isolates had a higher degree of similarity than with PFGE. The purK gene, which is one of the targets of the E. faecium multilocus sequence typing scheme, was sequenced. Eleven different purK alleles could be discerned, with the majority of isolates (n = 80) harboring allele 1. With only two exceptions, all strains carrying purK-1 clustered in the same PFGE and AFLP groups, indicating a good correlation between PFGE type, AFLP type, and purK allele. Genetic polymorphism of a 571-bp PCR fragment of the C-terminal domain of the penicillin-binding protein 5 gene (pbp5) was determined, and sequence differences were associated with the level of ampicillin resistance. This study indicates that the majority of ampicillin-resistant E. faecium strains in Norway belong to a distinct genetic lineage of closely related genotypes. Rectal and clinical isolates were generally indistinguishable, and differences in clonal distribution and allele polymorphism were found mainly between ampicillin-resistant and -susceptible isolates.

Assays for serological diagnosis of HSV-2 infection in clinical settings have been generally available only recently. We wanted to investigate and compare the diagnostic utility of three different ELISAs for detection of anti-HSV-2 IgG antibodies, using intact glycoprotein G or an oligopeptide from a portion of the protein as antigens. HSV-1 negative/HSV-2 negative sera (n = 32), HSV-1 positive/HSV-2 negative sera (n = 30) and sera from HSV-2 culture positive individuals (n = 36), collected at least 6 months after culture verified HSV-2 genital infection were examined. Cut-off values were determined according to the manufacturer's instructions, and also by establishing new cut-off values at the level of highest diagnostic efficiency. Sensitivities and specificities were compared for each assay. In addition, test accuracies were compared using receiver-operating characteristics (ROC) methodology. Establishment of new cut-off values increased the performance characteristics for all three tests. At similarly set cut-off values, the peptide 55 assay showed the highest diagnostic sensitivity (100%) and specificity (98%). All three assays displayed high efficiency and also high agreement between the tests (kappa > 0.85 for all comparisons). The performance of all three assays were satisfactory although the highest efficiency and accuracy was obtained with the peptide 55 assay., (Copyright 2002 Elsevier Science B.V.)

Poliomyelitis is a viral infection that causes flaccid paralysis in approximately 1% of cases. The Fc receptors for immunoglobulin G (FcgammaR) are associated with modifying effects of several infectious and autoimmune diseases. To assess the influence of FcgammaR polymorphisms on the acute and late course of poliomyelitis, 110 Norwegian patients with well-defined histories of acute poliomyelitis were genotyped, of whom 50 suffered from the postpolio syndrome (PPS). In comparison with healthy control subjects without a history of poliomyelitis, significantly fewer patients had the FcgammaRIIIA genotype V/V (P<.01). However, this genotype was not an independent risk factor for PPS. The FcgammaRIIA and IIIB genotypes and allele frequencies did not differ between the patients and control subjects. The FcgammaRIIIA V/V genotype may lower the risk for contracting acute poliomyelitis through better clearance of poliovirus.

Highly active antiretroviral therapy (HAART) can effectively suppress HIV-1 replication but, as soon as the drugs are withdrawn, there is a rapid rebound of replicating virus. Severe metabolic toxicities and therapy failures due to the appearance of resistant virus are becoming an increasing problem that precludes long-term continuous medication. Therapeutic immunizations represent a feasible and attractive means of supplementing or, alternatively, replacing current therapies, thereby reducing the potential for emergence of drug-resistant HIV-1 strains. We have performed an open, single-center, phase I safety study of a candidate therapeutic HIV-1 vaccine, Vacc-4x, given to 11 HIV-1-infected individuals with or without antiretroviral therapy. The immunogen consists of four synthetic peptides based on the major core protein p24. To ensure optimal exposure of the immunogen to the antigen-presenting cells (APCs), the vaccine was given intradermally together with granulocyte-macrophage colony-stimulating factor (GM-CSF). Responses to the immunization protocol were determined by delayed-type hypersensitivity (DTH) reaction, interferon gamma-secreting cells in the enzyme-linked immunospot (ELISpot) assay, and antibody production to the p24 protein and the peptides. The vaccine was safe and in general well tolerated. Plasma HIV RNA levels and CD4(+) cell counts did not change appreciably during the study. All patients showed a positive DTH response. For two of the patients, the immunization protocol induced responses to one or two of the tested peptides whereas a third patient showed reactivity to one of the peptides before immunization. A weak antibody response in the peptide-specific enzyme-linked immunosorbent assay could be seen in seven patients.

Background: Genital ulcer disease (GUD) is common in many developing countries. Several reports indicate that there is an association with HIV infection. Analysis by polymerase chain reaction (PCR) has demonstrated that the ulcers are frequently caused by herpes simplex type 2 (HSV-2), although HSV-1 is becoming increasingly important in many parts of the world. Comparable studies have not been performed in Tanzania., Objectives: To determine the prevalence of HSV-2 and HSV-1 in genital ulcers in Dar es Salaam, Tanzania and determine their possible association with HIV infection., Study Design: Samples were collected from 70 consecutive patients with GUD attending a clinic for sexually transmitted diseases. Specimens from ulcers were analysed by PCR for the presence of HSV-2 and HSV-1, and sera were examined for antibodies against HSV-2 and HIV., Results and Discussion: HSV-2 DNA was detected in 64% of the specimens from ulcers while HSV-1 DNA was not found in any of them. Antibodies to HSV-2 and HIV were detected in 79.7 and 42% of the patients' sera, respectively. Although there was a significant positive association between HIV and HSV-2 seropositivity, HSV-2 DNA in genital ulcers was not more prevalent among HIV seropositive than among HIV seronegative individuals., Conclusion: The prevalence of HSV-2 antibodies among Tanzanian patients with genital ulcers is very high, and HSV-2 is detected in most of the ulcers. There is an association between infections with HIV and HSV-2, but the relationship is not clear.

Objective: To examine patients with previous nonparalytic poliomyelitis in search of muscle atrophy, weakness, and other late symptoms of poliomyelitis., Design: A mailed questionnaire followed up with neurologic and neurophysiologic examinations of respondents who reported symptoms possibly related to the late sequelae of polio., Setting: Neurology department at a university hospital., Participants: Thirty-nine of 47 patients diagnosed with nonparalytic poliomyelitis and hospitalized at a Norwegian hospital between 1950 and 1954, during the Norwegian polio epidemic., Interventions: Not applicable., Main Outcome Measures: Electromyography to determine function of the anterior tibialis, vastus lateralis, and biceps brachii muscles; nerve conduction studies of the sural, peroneal, and tibial nerves; motor and sensory nerve conduction velocity, and compound muscle and sensory nerve action potentials, and distal latencies., Results: Twenty-five of 47 patients (53.2%) reported symptoms possibly related to the late sequelae of poliomyelitis. Eight of 20 examined symptomatic patients had normal neurologic and neurophysiologic findings, whereas 9 others had other medical conditions that could explain the symptoms. Three patients (6.7%) had neurologic and neurophysiologic findings and development of symptoms consistent with motoneuron damage., Conclusion: Some nonparalytic patients may have subclinical acute motoneuron damage with subsequent development and manifestation of motor weakness and neuromuscular symptoms many years later. These symptoms should be considered a differential diagnosis in patients who have a history of nonparalytic poliomyelitis., (Copyright 2002 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation)